Southern California -- this just in

Proponents of a ballot measure that banned same-sex marriage filed a lawsuit in federal court this week seeking to overturn state campaign finance laws that require that names and personal information of donors to state political campaigns be made public.

They claimed that donors to Proposition 8, which banned same-sex marriage in California after one of the most heated campaigns in recent memory, have been the victim of threats and harassment because of their support for ending same-sex marriage was made public.

“This harassment is made possible because of California’s unconstitutional campaign finance disclosure rules as applied to ballot measure committees where even donors of as little as $100 must have their names, home addresses and employers listed on public documents,” Ron Prentice, head of the Protect Marriage Coalition, said in a statement.

Since 1974, state law has required that donors who give more than $100 must have their names disclosed.

The law was intended to prevent money laundering and to provide disclosure of who is making contributions to political campaigns. It has withstood several previous legal challenges. Experts on the 1st Amendment experts said they did not believe the suit stood much of a chance of success.

“This trashes the 1st Amendment and it is a thinly veiled attempt to eliminate transparency as to the role of money in state election campaigns,” said Mark Rosenbaum, legal director of the ACLU of Southern California. The ACLU was a major opponent of Proposition 8.